Ultrasonic Ranging Module HC – SR04
Product features
Ultrasonic ranging module HC – SR04 provides 2cm – 400cm non-contact measurement function, the ranging accuracy can reach to 3mm. The modules includes ultrasonic transmitters, receiver and control circuit.
The basic principle of work:
(1) Using IO trigger for at least 10us high level signal,
(2) The Module automatically sends eight 40 kHz and detect whether there is a pulse signal back.
(3) IF the signal back, through high level , time of high output IO duration is the time from sending ultrasonic to returning.
Test distance = (high level time×velocity of sound (340M/S) / 2,
Wire connecting direct as following
5V Supply
Trigger Pulse Input
Echo Pulse Output
0V Ground

Electric Parameter
Working Voltage: DC 5 V
Working Current: 15mA
Working Frequency: 40Hz
Max Range: 4m
Min Range: 2cm
MeasuringAngle: 15 degree
Trigger Input Signal: 10uS TTL pulse
Echo Output Signal: Input TTL lever signal and the range in proportion
Attention
The module is not suggested to connect directly to electric, if connected electric, the GND terminal should be connected the module first, otherwise,it will affect the normal work of the module.
When tested objects, the range of area is not less than 0.5 square meters and the plane requests as smooth as possible, otherwise ,it will affect the results of measuring.